An agricultural tractor is usually driven rather slowly when pulling an implement and the tractor stops on disengagement of the clutch. However, the gears on the input shaft and connected structure, such as the clutch plate and a countershaft often continue to rotate after the clutch is disengages since there is nothing to stop them. If the gears are not synchronized, the operator has either to clash gears and attempt to change speed or wait until the gears slow down before shifting. This may take some time if the gears are not stopped by braking means. With synchronization there is no clashing of the spinning gears as the gears to be meshed are brought to the same speed. However, although synchronization is readily available for smaller and lighter duty transmission, it is often not useful for larger transmission components. For this reason, not only is synchronizing of heavier transmission components apt to be more expensive, but the loads imposed by synchronizer mechanisms and gear trains on the shift linkage can undesireably increase the shifting effort required. A transmission brake thus often is more desirable. It is desirable that the transmission brake be compact and take as little of the length of the tractor as possible.